Q. 24.4( 49 Votes )

# In each of the following, find the equation of the circle with

Centre (–2,3) and radius 4

Answer :

The equation of a circle with centre (h,k) and radius r is given as

(x-h)^{2} + (y-k)^{2}=r^{2}

It is given that centre (h,K) = (-2,3) and radius (r) =4

Therefore, the equation of the circle is

(x+2)^{2} + (y-3)^{2} = (4)^{2}

⇒ x^{2} + 4x + 4 + y^{2} - 6y + 9 = 16

⇒ x^{2} + y^{2} + 4x - 6y - 3 = 0

Therefore, the equation of the circle is x^{2} + y^{2} + 4x - 6y - 3 = 0

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